As I mentioned the other day in a design discussion, I think the panel (and everything) should be scalable according to the screen DPI. And we should have an option to configure/change the screen DPI value.

Thank you for taking the time to report this bug. We have tried to recreate this on the latest release of Ubuntu, but cannot reproduce it. This bug is being marked as Invalid. If you believe the problem to still exist in the latest version of Ubuntu, please comment on why that is the case and change the bug status to NEW.

Go to "Settings" -> "Screen Display" and adjust the slider labelled "Scale for menu and title bars:". Both text and icons are scaled.